Researching periodontitis: challenges and opportunities

The expression and clinical significance of miR-1226 in patients with periodontitis

Background

miR-1226 has been reported to be dysregulated in periodontitis, implying its potential functional role, which needs to be validated. The purpose of this study was to assess the clinical significance of miR-1226 in periodontitis.

Methods

Gingival crevicular fluid samples were collected from 50 healthy volunteers and 72 periodontitis patients. The expression of miR-1226 in collected samples was detected by RT-qPCR. The concentrations of pro-inflammatory cytokines were analyzed by ELISA. The relationship of miR-1226 expression level with patients’ characteristics was evaluated by the χ² test and the Pearson correlation test.

Results

It was found that miR-1226 was downregulated in the gingival crevicular fluid of periodontitis patients compared with healthy volunteers. The downregulation of miR-1226 was negatively correlated with the pocket depth, attachment loss, plaque index, bleeding index, and MMP-8 concentration of patients. miR-1226 showed high sensitivity and specificity to discriminate periodontitis patients from healthy volunteers. Additionally, periodontitis patients had a relatively high concentration of pro-inflammatory cytokines, which is correlated with miR-1226 expression negatively.

Conclusions

miR-1226 could be an indicator for the diagnosis of periodontitis and has the potential to predict the development and severity of periodontitis.

Periodontitis is associated with significant hepatic fibrosis in patients with non-alcoholic fatty liver disease

Background and aims

Non-alcoholic fatty liver disease (NAFLD) has a bidirectional association with metabolic syndrome. It affects up to 30% of the general population, 70% of individuals with diabetes and 90% with obesity. The main histological hallmark of progressive NAFLD is fibrosis. There is a bidirectional epidemiological link between periodontitis and metabolic syndrome. NAFLD, periodontitis and diabetes share common risk factors, are characterised by inflammation and associated with changes in commensal bacteria. Therefore we tested the hypothesis that periodontitis is associated with NAFLD and with significant fibrosis in two study groups.

Methods

We analyzed data from a population-based survey and a patient-based study. NHANES III participants with abdominal ultrasound and sociodemographic, clinical, and oral examination data were extracted and appropriate weighting applied. In a separate patient-based study, consenting patients with biopsy-proved NAFLD (or with liver indices too mild to justify biopsy) underwent dental examination. Basic Periodontal Examination score was recorded.

Results

In NHANES, periodontitis was significantly associated with steatosis in 8172 adults even after adjusting for sociodemographic factors. However, associations were fully explained after accounting for features of metabolic syndrome. In the patient-based study, periodontitis was significantly more common in patients with biopsy-proven NASH and any fibrosis (F0-F4) than without NASH (p = 0.009). Periodontitis was more common in patients with NASH and significant fibrosis (F2-4) than mild or no fibrosis (F0-1, p = 0.04).

Conclusions

Complementary evidence from an epidemiological survey and a clinical study show that NAFLD is associated with periodontitis and that the association is stronger with significant liver fibrosis.

Temporal sequence of the bidirectional relationship between hyperglycemia and periodontal disease: a community-based study of 5,885 Taiwanese aged 35-44 years (KCIS No. 32)

The relationship between hyperglycemia (including diabetes) and periodontal disease (PD) has been noted previously, but its temporal sequence in the same study based on a population-based study has been barely addressed. Our study sought to clarify temporal bidirectional relationships between both diseases among Taiwanese aged 35-44 years. A prospective follow-up cohort study was designed by following over time the two normal cohorts (PD-free or hyperglycemia-free) derived from 5,885 subjects aged 35-44 years who were periodically attending a screening program. We ascertained both incident cases of PD (defined by Community Periodontal Index score ≧ 3) and hyperglycemia [fasting plasma glucose (FPG) ≧100 mg/dL] or type 2 diabetes (FPG ≧ 126 mg/dL) with 5-year follow-up. Cox proportional hazards regression model was used to assess the effect of PD on hyperglycemia and vice versa with adjustment for other confounding factors. Participants with PD presented a 33 % increase in their risk of incident hyperglycemia (including diabetes) [adjusted hazard ratio (aHR) = 1.33 (95 % CI 1.09-1.63)] after controlling for potential confounding factors. Conversely, prediabetes and type 2 diabetes mellitus led to a significant elevated risk for PD [aHR = 1.25 (95 % CI 1.00-1.57) and aHR = 1.95 (95 % CI 1.22-3.13)] after adjustment for other confounding factors. In conclusion, a significant bidirectional relationships was found between hyperglycemia and PD, suggesting that both diseases may share common latent traits and pathways that are worthy of being further elucidated by continuing a long-term follow-up of this cohort.

Accuracy of self-reported periodontal disease in the Women's Health Initiative Observational Study

BACKGROUND

This study examines the accuracy of self-reported periodontal disease in a cohort of older females.

METHODS

The study comprised 972 postmenopausal females aged 53 to 83 years who completed baseline (1997 to 2001) and follow-up (2002 to 2006) whole-mouth oral examinations. Examinations included: 1) probing depth, 2) clinical attachment level, and 3) oral radiographs for alveolar crestal height in a study ancillary to the Women's Health Initiative Observational Study (WHI-OS) conducted in Buffalo, New York, called the OsteoPerio study. Participants also self-reported any history of diagnosis of periodontal/gum disease on a WHI-OS study-wide questionnaire administered during the time interval between the two OsteoPerio examinations.

RESULTS

Participants reporting diagnosis of periodontal/gum disease on the WHI-OS questionnaire (n = 259; 26.6%) had worse oral hygiene habits, periodontal disease risk factors, and clinical periodontal measures compared with those not reporting periodontal/gum disease. Frequency of reported periodontal/gum disease was 13.5%, 24.7%, and 56.2% across OsteoPerio baseline examination categories of none/mild, moderate, and severe periodontal disease, respectively (trend: P <0.001), defined by criteria of the Centers for Disease Control and Prevention/American Academy of Periodontology (CDC/AAP). Sensitivity, specificity, and positive and negative predictive values for reported periodontal disease status were 56.2%, 78.8%, 32.8%, and 90.7%, respectively, when CDC/AAP-defined severe periodontal disease at baseline was the criterion measure (prevalence of 15%) and were 76.0%, 77.4%, 22.0%, and 97.4%, respectively, when tooth loss to periodontitis (prevalence of 7%) was the criterion.

CONCLUSION

A simple question for self-reported periodontal disease characterizes periodontal disease prevalence with moderate accuracy in postmenopausal females who regularly visit their dentist, particularly in those with more severe disease.

Periodontal diagnosis affected by variation in terminology

BACKGROUND

The randomized case presentation (RCP) study is designed to assess the degree of diagnostic accuracy for described periodontal cases. This is to lay the basis for practitioner calibration in the Practitioners Engaged in Applied Research and Learning (PEARL) Network for future clinical studies.

METHODS

The RCP consisted of 10 case scenarios ranging from periodontal health to gingivitis and mild, moderate, and severe periodontitis. Respondents were asked to diagnose the described cases. Survey diagnoses were compared to two existing classifications of periodontal disease status. The RCP was administered via a proprietary electronic data capture system maintained by the PEARL Data Coordinating Center. Standard analytic techniques, including frequency counts and cross-tabulations, were used for categorical data with mean and standard deviation and median values reported for continuous data elements.

RESULTS

Demonstrable variations in periodontal assessment for health, gingivitis, and mild, moderate, and severe periodontitis were found among the 130 PEARL general practitioners who participated in the RCP survey. The highest agreement for diagnosis among dentists was for severe periodontitis (88%) and the lowest for gingivitis (55%). The highest percentage of variation was found in cases with health and gingivitis.

CONCLUSIONS

There was variation among PEARL practitioners in periodontal diagnosis that may affect treatment outcomes. Our findings add clinical support to recent publications suggesting a need for standardization of terminology in periodontitis diagnosis.

Five-year changes in periodontal disease measures among postmenopausal females: the Buffalo OsteoPerio study

BACKGROUND

Understanding of longitudinal characteristics of periodontal disease in older females is limited. This study examined 5-year changes in periodontal disease measures among postmenopausal females.

METHODS

Participants were 1,025 postmenopausal, 53- to 83-year-old females who completed baseline (1997 to 2001) and 5-year follow-up (2002 to 2006) whole-mouth oral examinations in a study ancillary to the Women's Health Initiative. Periodontal disease was characterized using probing depth (PD), clinical attachment level (CAL), alveolar crest height (ACH), and tooth loss. Differences in measures between examinations were used to characterize patterns of change.

RESULTS

Baseline prevalence of none/mild, moderate, and severe periodontal disease defined using criteria of the Centers for Disease Control and Prevention was 27%, 58%, and 15%, respectively. Tooth loss attributable to periodontitis occurred in 13% of females. Mean ± SD changes in whole-mouth mean measures showed progression when based on ACH (-0.19 ± 0.49 mm) yet relatively stable disease when based on PD (0.11 ± 0.42 mm) and CAL (0.06 ± 0.58 mm). Mean change in worst-site ACH was greater (P <0.001) in females with severe periodontitis and osteoporosis at baseline and with tooth loss during follow-up. Periodontal changes did not differ according to baseline age, hormone therapy use, smoking status, or age at menopause.

CONCLUSIONS

Five-year changes in periodontal measures among generally healthy postmenopausal females were, on average, small and did not suggest a consistent pattern of disease progression. Females with history of severe periodontitis or osteoporosis may experience accelerated oral bone loss despite stability or small improvement in routine probing measures.

Effect of scaling and root planing on interleukin-1β, interleukin-8 and MMP-8 levels in gingival crevicular fluid from chronic periodontitis patients

BACKGROUND AND OBJECTIVE

  There are few data concerning the effect of scaling and root planing on the levels of immune and inflammatory mediators in gingival crevicular fluid from patients with chronic periodontitis. Therefore, in this study the influence of scaling and root planing was determined on amounts of interleukin (IL)-1β, IL-8 and MMP-8 in gingival crevicular fluid from patients with chronic periodontitis, in relation to clinical parameters.

MATERIAL AND METHODS

  A total of 51 patients were enrolled in this study. The study population consisted of 30 patients with generalized advanced chronic periodontitis, while 21 periodontally healthy subjects were recruited for the control group. The clinical parameters included approximal plaque index, gingival index, pocket depth and clinical attachment loss. The amounts of IL-1β, IL-8 and MMP-8 in gingival crevicular fluid were measured by ELISA. Periodontal parameters as well as gingival crevicular fluid humoral factor amounts were evaluated in the control group and in chronic periodontitis patients at baseline and at 1 and 4 wk after scaling and root planing treatment.

RESULTS

  At baseline, there were significant differences between control subjects and chronic periodontitis patients in terms of clinical attachment loss, pocket depth, gingival index (p < 0.001) and approximal plaque index (p < 0.01). The amounts of IL-1β, MMP-8 (p < 0.001) and IL-8 (p < 0.01) in gingival crevicular fluid were significantly lower in healthy subjects than in chronic periodontitis patients. Scaling and root planing led to improvement in all examined clinical parameters, apart from clinical attachment loss. Periodontal treatment also resulted in a significant decrease in the amounts of IL-1β, IL-8 and MMP-8 in comparison to baseline, especially 4 wk after scaling and root planing (p < 0.001); however, the amounts of these humoral factors were still higher than those in control group.

CONCLUSION

Our observations indicated that short-term nonsurgical therapy resulted in a significant improvement in periodontal indices and in a marked decrease of IL-1β, IL-8 and MMP-8 gingival crevicular fluid levels. Nevertheless, no significant correlations were found between clinical parameters and amounts of humoral factors after therapy.

"Evidence-based dentistry in oral surgery: could we do better?"

Evidence-based Dentistry (EBD), like Evidence-based Medicine (EBM), was born in order to seek the “best available research evidence” in the field of dentistry both in research and clinical routine.

But evidence is not clearly measurable in all fields of healthcare: in particular, while drug effect is rather independent from clinician’s characteristics, the effectiveness of surgical procedures is strictly related to surgeon’s expertise, which is difficult to quantify. The research problems of dentistry have a lot in common with other surgical fields, where at the moment the best therapeutic recommendations and guidelines originates from an integration of evidence-based medicine and data from consensus conferences.

To cope with these problems, new instruments have been developed, aimed at standardizing clinical procedures (CAD-CAM technology) and at integrating EBM achievements with the opinions of expert clinicians (GRADE System).

One thing we have to remember however: it is necessary to use the instruments developed by evidence-based medicine but is impossible to produce sound knowledge without considering clinical expertise and quality of surgical procedures simultaneously. Only in this way we will obtain an evidence-based dentistry both in dental research and clinical practice, which is up to third millennium standards.

“Evidence-Based Dentistry in Oral Surgery: Could We Do Better?”

Evidence-based Dentistry (EBD), like Evidence-based Medicine (EBM), was born in order to seek the “best available research evidence” in the field of dentistry both in research and clinical routine.

But evidence is not clearly measurable in all fields of healthcare: in particular, while drug effect is rather independent from clinician’s characteristics, the effectiveness of surgical procedures is strictly related to surgeon’s expertise, which is difficult to quantify. The research problems of dentistry have a lot in common with other surgical fields, where at the moment the best therapeutic recommendations and guidelines originates from an integration of evidence-based medicine and data from consensus conferences.

To cope with these problems, new instruments have been developed, aimed at standardizing clinical procedures (CAD-CAM technology) and at integrating EBM achievements with the opinions of expert clinicians (GRADE System).

One thing we have to remember however: it is necessary to use the instruments developed by evidence-based medicine but is impossible to produce sound knowledge without considering clinical expertise and quality of surgical procedures simultaneously. Only in this way we will obtain an evidence-based dentistry both in dental research and clinical practice, which is up to third millennium standards.

Inverse association between periodontitis and respiratory allergies in patients with type 1 diabetes mellitus

AIM

In a general adult population, we have demonstrated an inverse association between periodontitis and respiratory allergies that is in line with the hygiene hypothesis suggesting a protective effect of infections against the development of allergies. The objective of the present study was to investigate the association between periodontitis and respiratory allergies in a type 1 diabetes mellitus population.

MATERIAL AND METHODS

The study population comprised 170 patients with type 1 diabetes mellitus aged 17-80 years. Respiratory allergies were present in 22 subjects. The attachment loss (AL) was measured. Periodontitis was defined according to the percentage of surfaces that exceeded 3 mm AL (healthy, mild, moderate, severe periodontal conditions).

RESULTS

Our adjusted analyses revealed an inverse association between periodontitis and respiratory allergies. For increasing AL, a trend towards a decreasing risk was present for respiratory allergies (p(trend)<0.05). Compared with subjects with healthy periodontal conditions, individuals with severe periodontal conditions had the lowest risk of respiratory allergies [odds ratios (OR) 0.06 (95% confidence interval (CI) 0.01-0.39)], followed by subjects with moderate AL [OR 0.14 (95% CI 0.03-0.63)] and mild AL [OR 0.32 (95% CI 0.09-1.08)].

CONCLUSION

There is a strong inverse association between periodontitis and respiratory allergies in patients with type 1 diabetes mellitus. These findings further support the hygiene hypothesis.